In designing ballistic helmets there is an ongoing desire to attach peripheral elements such as equipment rails, night vision goggles and night vision goggle shrouds, communication devices, hearing protection devices, and the like.
On the one hand, companies such as 3M have been technology leaders in designing ballistic helmets that allow for connecting such peripheral elements without penetrating the helmet's ballistic layer. On the other hand, helmets are still made, whether for ease of manufacturing, cost, weight, or flexibility of design, with through-holes and connection points that penetrate the helmet ballistic layer. When such sites of ballistic layer compromise are present, it is required that any peripheral element connected through such through-hole be connected with ballistic rated connection elements.